The invention relates to a protective element for a wearing-part attachment for a wearing part for a leading edge of a working member of an earth-working implement, the wearing part and the wearing-part attachment being provided with complementary quick-coupling elements, and a leading side surface of the protection element including a wearing portion. Further, the invention relates to a method of wear-protecting a wearing-part attachment for a wearing part for a leading edge of a working member of an earth-working implement, the wearing part and the wearing-part attachment being provided with complementary quick-coupling elements.
Earth-working implements, for example ploughs, harrows, excavator buckets and so on, are often provided with replaceable wearing parts in the form of wearing points, teeth and so on. To facilitate the replacement of such wearing parts, it is known to attach the wearing part to a wearing-part attachment by means of a quick-coupling. To have a desired effect of the quick-coupling system, it is obvious that the lifetime of the wearing-part attachment must be at least double the lifetime of the wearing part. In practice, it has turned out that extraordinary precautions must be taken at the wearing-part attachment to achieve the desired lifetime. The precautions may include applying a harder material, for example by hardfacing with a hard-metal coating or soldering with hard-metal elements, to the surface or surfaces of the wearing-part attachment that is/are subjected to the greatest wear, typically portions facing the material flow passing the wearing-part attachment.
Welding or soldering involves the necessity of supplying a relatively large amount of heat energy to the wearing-part attachment for the wearing-part attachment to achieve the desired temperature so that a sufficiently good adherence is provided between the hard metal and the wearing-part attachment. It is known in the art that a great difference in mass between the elements that are to be joined is disadvantageous. For example, if the wearing-part attachment has been hardened prior to the application of hard metal, the supply of heat may take the hardening out of an unduly large portion of the wearing-part attachment. A similar problem is associated with treating the wearing-part attachment with other materials, for example carbon to carbidize a portion of the wearing-part attachment, or nitrogen to nitrate a portion of the wearing-part attachment.